Programmable read-only memory devices have numerous applications in modern semiconductor structures. Among the devices which can be particularly useful are EPROM and EEPROM devices, which can store information in read-only format and yet enable the information stored therein to be erased by subjecting the memory devices to appropriate energy. The energy utilized to erase EPROM devices is typically ultraviolet (UV) radiation, whereas the energy utilized to erase EEPROM devices is electrical energy. A flash device is typically an EEPROM device, with the term “flash” indicating that the device can be erased within a time of less than or equal to 2 seconds.
It is desired to develop improved methods for forming programmable read-only memory devices.